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| 1 | Removal of damaged concrete along with loose damaged and cracked concrete/cover concrete at all specified locations up to beyond the corroded steel reinforcements to a depth of 10 mm minimum behind the reinforcement by chipping/hacking with chisel and hammer or by mechanical means like chisel hammer, pneumatic chippers including high pressure water jetting to chipped concrete and reinforcement and removal and disposal of debris within owners premises including all plant and machineries. Hard concrete shall not be removed. However if the rebar is corroded, concrete around it shall be removed. Depth of chipping may very from 50 mm to 150 mm complete with labour, machinery, tools etc. all as directed by Engg.in charge. The edges of repair location shall be saw cut to a depth of at least 10 mm to avoid feather edging and provide a square edge. Removal of dust, loose particles, marine growth etc. from concrete surface manually by wire brush, mechanically or any other means to obtain a sound surface over areas other than above. Item rate is inclusive of materials all labour, tools and tackles, and transportation etc. complete as per specification and as directed by Engg.-in-charge. |
| 2 | Providing & applying inhibition coats/system to exposed reinforcement bars after drying & also new bars after cleaning & removing scales and rust completely as specified. An Anti corrosive coat contents Active 'Zinc-rich' system which combats corrosion by electro chemical means. having specific gravity of 1.75, Adhesive bond strength > 1.5 N/mm2 Zinc content >84 % by weight, 40 microns DFT, Fully dry/ Recoatable - 45 minutes to 1 hour. Typical application includes surface preparations by cleaning steel surface to a bright condition paying particular attention to the back of exposed steel bars, mixed two components slow speed heavy duty drill fitted with a paddle, applying unbroken coat with suitable brush and allow to dry, after 30 mins apply second coat to ensure complete cover to exposed steel/ rebar etc complete. Total Dry film thickness is 40 microns. Item rate is inclusive of materials all labour, tools and tackles, and transportation etc. complete as per specification and as directed by Engg.-in-charge. |
| 3 | Providing and applying Epoxy bonding agent on the prepared surface to receive polymer modified mortar/polymer modified micro concrete, with two component epoxy based bonding coat , having Compressive strength(BS 6319 Pt.2)- 40 Mpa at 7 days, Flexural strength strength(BS 6319 Pt.3)- 25 Mpa at 7 days, Tensile strength (BS 6319 Pt.7)- 15 Mpa at 7 days, Bond Strength (ASTM C881)- 11 Mpa at 7 days, having an over lay time of 3 Hrs at 35 °C. Laying of reinstatement polymer modified mortar or micro concrete shall be completed within the overlay time of bonding coat. The bond coat act as a bonding coat between old and new concrete. Item rate is inclusive of materials all labour, tools and tackles, Shuttering Supporting material and transportation etc. complete as per specification and as directed by Engg.-in-charge. |
| 4 | Concrete Mortar :-Supplying and providing 50mm thick concrete using cement, sand and 6mm down aggregates in proportion 1:1.5:3 admixed with Waterproofing concrete/mortar admixture confirming to IS:2645 and IS:9103 in proportion as recommended by manufacturer (as per Annexure-1) including cost of all labour, material, T&P etc. complete. |
| 5 | Providing and laying shrinkage controlled polymer modified single component, alkaline resistant fibre reinforced, thixotropic, cementitious patch repair mortar supplied in moisture resistant bag when mixed with clean water at w:p ratio 0.18, achieves compressive strength (BS 1881 Pt.116) -> 20 Mpa at 1 day & > 45 Mpa at 28 days, Tensile Strength(BS 6319 Pt.7) > 2.5 Mpa at 28 Days, Flexural Strength(BS 6319 Pt.3)>7 Mpa at 28 days, Drying shrinkage to ASTM C 157-93, 28 days < 1000 microstrain. Typical application inclues mixing entire bag with clean water about 4.25L to 4.5 L, mixed in suitable container with heavy duty slow speed mixer machine to achieve uniform lump free mortar consistency, placing and finishing the same with trowel carefully compacting the same around the rebars and finishing to bring it in line with existing concrete surface on the beams, slabs, piles etc., where the thickness of application is less than 50 mm in patches as per specification after applying bonding coat. Item rate is inclusive of materials all labour, tools and tackles, and transportation etc. complete as per specification and as directed by Engg.-in-charge. Payment shall be made as per actual site measurement. Please Enable Macros to View BoQ information |
